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Lacey Spears Trial: Did a suburban mom kill her five year old boy?

NEW YORK - On January 17, 2014, Lacey Spears of Chestnut Ridge, N.Y., rushed her 5-year-old son, Garnett, to Nyack Hospital. He was taken to the ER and then admitted to the hospital. Lacey told doctors he was suffering from seizures and had a bad headache. For two weeks before he died, Lacey told friends, Garnett's teacher and doctors that he had been sick with the flu, high fever, and worst of all, seizures.

The case against her for allegedly killing the boy is being laid out this week in her trial in White Plains, New York.

Lacey Spears went to her pediatrician who told her Garnett was fine, then took the boy to a local hospital, The hospital did a full workup and did not detect seizures either, said he was normal, fine but... his sodium level was a little high and magnesium and sugar levels were a bit off.

Lacey Spears and her son, Garnett Facebook via CBS New York

Three days later she took him to her pediatrician who also said the child was fine, normal. Once home, Garnett had another seizure -- writhing on the floor -- complaining of a stomach ache, headache and pain. Lacey got into the car and drove him to Nyack Hospital, a bigger facility with a pediatric neurologist and other specialists on staff.

Her pediatrician also had privileges there.

A doctor and triage nurse both examined Garnett, and other than a little hand trembling they did not see any indication of seizures, either. To be safe, they admitted Garnett and hooked him up to a video EEG to monitor brain activity throughout the evening and next two days. His salt level was considered fine. They continually monitored him throughout the day and by all accounts he was getting better - playing on the bed with mom, drawing, reading, walking, standing and eating. Lacey was by his side all day, all night. Several hours later he started complaining of pain, jerking his legs up, spasmodic movements, and though doctors said it was not a seizure, something did happen.

They know because there was video watching Garnett and Lacey Spears for the 40 hours they were there. However, the audio didn't work right so inside the courtroom, from a distance, one cannot fully understand what is being said. On Sunday, January, 19, 2014, Garnett was is critical condition with an excessively high salt level -- such a high level that doctors at both Nyack Hospital and Westchester Medical Center did not believe a sodium level that high was compatible with life. He should be dead, the doctors believed.

Garnett was airlifted to Westchester Medical Center where he died on January 23.

The initial cause of death was listed by the coroner as undetermined. Months later, it was changed to hypernatremia, also known as salt poisoning.

The crux of the case is this: What caused such a high level of sodium in his system? Could any other metabolic abnormality have caused the seizures? Or did Lacey intentionally kill her child?

Lacey Spears speaks to her lawyers in the Westchester County Courthouse, Thursday, Dec. 11, 2014 in White Plains, N.Y. Ricky Flores, AP

In opening arguments on Feb. 3, 2015, defense attorney Steven Reibling told the jurors -- many of whom have children -- that it's okay to grieve for Garnett, to shed tears, to feel anger and frustration, that's what makes us human...but he also asked the jury to separate emotions from rational thinking and listen to the facts. He argued that Lacey Spears is a loving and devoted mother who did everything she could to find care and treatment for her sick son -- took him to the doctor, to the hospital, and researched on the internet items including the effects of "too much sodium on a child" and "impact of high magnesium level"... "what does high sugar mean for a child" and "Can high magnesium, sugar, and salt cause seizures?" She did everything you would expect a loving mother to do, he argued.

Reibling asked the jury to focus on the facts of the last few days, hours and minutes of Garnett's life. He told the jury there's no forensic evidence, no eyewitnesses, and no motive or Lacey Spears to kill her child.And he said the boy died because Nyack Hospital didn't have the expertise to manage his care, and didn't look at a number of other issues that could have explained some of his symptoms.

The prosecution, in opening arguments on February 2, told jurors Lacey Spears is not an innocent mother, but a cold, calculating child killer, no longer the mother of Garnett but the murderer of Garnett. Garnett was a child with special needs, and diagnosed at 9 months with failure to thrive, doctors placed a gastric tube in his abdomen and performed a surgical nissan fundoplication to stop him from regurgitating his food. He reportedly had many issues -- 23 hospitalizations in his short life alone. The prosecution suggests, however, that Garnett didn't need the gastric tube any longer, but rather his mother did -- to use as a weapon to introduce salt into his body to intentionally poison him.

Lacey Spears is charged with first degree manslaughter and second degree murder in Garnett's death, and her trial is approaching the one-week mark on Friday.